It's hit or miss. I recommend going early on Sunday for immediate seating. Otherwise during prime breakfast/bunch time 9-12 on a weekend it could be a 10-25 minute wait. You can also call ahead to put your name on the list. It gives you more of a priority for seating, but it's not a reservation system.
My experience has been that, on Saturdays after 9:30 a.m., it often takes anywhere from 15 to 20-some minutes to be seated. However, once seated, the service is surprisingly quick--unless you order the pannekoeken, which they warn takes 20 minutes to cook (but worth it if you have the time).
We went on Monday around 11:30 am and our wait was very short, only minutes from walking in the door to ordering. I will say that they weren't busy at this time.
Not long at all. In fact, I think we waited a minute before we were greeted by our server. This was my first time in MN, and I must say, this restaurant was great. You will enjoy the food and the atmosphere.
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